The competition for slots at the fire academy can be fierce--this article discusses how earning an EMT certification prior to applying could give you an advantage over the competition.
The best way to prepare for the process of becoming a citizen is to know what to expect. This article provides an overview of that process to help you get started on the right foot.
You can find help with becoming a U.S. citizen in many places. This article includes contact information for the USCIS Lockbox Facilities so you can find the one for your state. Other groups offer help too, and you'll find information on how to access that help.